[PATCH v4 0/5] Software ISP levels cleanup

[Kieran Bingham]

Quoting Milan Zamazal (2024-05-28 17:11:21)
> This is a cleanup of black level and color gain handling in software
> ISP.  It fixes omission of black level subtraction in white balance
> computation and moves color lookup tables computations out of
> debayering.  The latter also serves as a preparation for bringing
> software ISP algorithms closer to common libcamera algorithm handling,
> in future patches.
> 
> Changes in v4:
> - Removed no longer used private members of DebayerCpu.
> - Added initialization of SoftwareIsp::debayerParams_ (should fix the
>   initial color artifacts observed by Kieran).

Confirmed, 

Tested-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

And all green on CI:
 - https://gitlab.freedesktop.org/camera/libcamera/-/pipelines/1188426

--
Kieran



> Changes in v3:
> - Casting an uint8_t value to unsigned int when logging it. 
> 
> Changes in v2:
> - stdint.h include moved from black_level.cpp to black_level.h.
> - Removed meaningless multiplication in black level subtraction.
> - Removed local variable scoping block.
> - Added a comment about subtracting black level for auto white balance.
> - A code snippet related to black level subtraction moved to the right
>   patch.
> - Dropped the patch moving TODO #13 to a source code comment.
> - Added a patch to use float rather than uint8_t gains in color lookup
>   tables passed to debayering.
> 
> Milan Zamazal (5):
>   libcamera: software_isp: Use a specific integer type for black level
>   libcamera: software_isp: Honor black level in AWB
>   libcamera: software_isp: Move color mappings out of debayering
>   libcamera: software_isp: Remove DebayerParams::kGain10
>   libcamera: software_isp: Pass color lookup tables as floats
> 
>  .../internal/software_isp/debayer_params.h    | 20 ++---
>  src/ipa/simple/black_level.cpp                |  2 +-
>  src/ipa/simple/black_level.h                  |  5 +-
>  src/ipa/simple/soft_simple.cpp                | 74 ++++++++++++++-----
>  src/libcamera/software_isp/TODO               | 13 ----
>  src/libcamera/software_isp/debayer.cpp        | 33 ++++-----
>  src/libcamera/software_isp/debayer_cpu.cpp    | 55 +++++---------
>  src/libcamera/software_isp/debayer_cpu.h      | 15 ++--
>  src/libcamera/software_isp/software_isp.cpp   | 15 +++-
>  9 files changed, 125 insertions(+), 107 deletions(-)
> 
> -- 
> 2.42.0
>